In recent years, due to changes in land use, climate changes, and cultural practices, populations of several avian species, including the Canadian Goose, has increased. Associated with this increase in population, is damage to property as well as increased risks to human health and safety. Although these problems are on the rise, the number of management options available to control birds has been limited to non-lethal approaches. There are two types of Canadian geese that cause problems for residents, golf courses, public parks, airports, etc.—resident geese and non-resident geese. Resident geese have a small territory that they habituate annually and they do not migrate to Canada. Non-resident geese migrate to Canada annually. Geese will usually, at night, rest on the water, away from land predators, and spend a majority of their night resting on the water where it is safe.
Unlike migratory geese, resident Canada geese (Branta canadensis) breed and nest in the United States. From 1970 to 2010, resident Canada goose populations in the United States increased about 14-fold—from 250,000 to 3.5 million. In the Eastern United States alone, resident Canada goose populations exceed 1 million and have increased by 2 percent each year during the last 10 years. A main factor contributing to their dramatic population growth is their tendency to nest in urban and suburban areas, where the geese have ideal habitat with few predators and where hunting cannot be used to control the population. Geese prefer to land on water and to graze on grassy areas within sight of a body of water. Additionally, geese may concentrate nesting and brood rearing activities near water.
Homeowners, corporations, golf courses and farmers have sought ways to deter geese from inhabiting their property. Golf courses have used Border Collies, firecrackers, guns (blanks), decoys, balloons, wires, and general harassment. Farmers have tried propane exploders, scare flags, shell crackers, and hunters, all of which have proven unsuccessful at keeping geese from crops in the long term. Tests of early audio systems in agricultural fields deterred geese in some areas, while no effect was seen in others, and geese habituated to propane exploders as well. The distribution of Canada Geese is widespread, and their behavior has enabled them to thrive in urban settings. They therefore pose a greater potential risk to human health than other waterfowl. When congregations of birds remain in the same areas for long periods they can emaciate grass, nutrify soils (through excessive fecal deposits), and make public areas unusable for picnics, resting or general park activities.
The majority of Canada goose damage complaints involve accumulations of feces on lawns and walkways at homes, schools, hospitals, corporate campuses, and public parks. Goose feces damage property, compromise overall quality of life, and have the potential to pose serious health threats due to the presence of disease-causing organisms. Bird strikes—the collision between birds and aircraft—are among the most common aviation hazards. Bird strikes pose safety risks to passengers (e.g., 23 human deaths and 223 injuries from 1990 to 2011 in USA). With increases in the number of routes and flights, this threat is on the rise. Collisions between birds and aircraft (bird strikes) are expensive, risk human lives, and increase bird mortality.
Other damage associated with geese includes overgrazing of lawns and recreational fields, and goose aggression and human injury during the nesting season.
Waterfowl such as Canada geese may also pose serious flight safety hazards at airports. Due to their large body size, flocking behavior, and relative abundance in urban/suburban areas, geese have the potential to be involved in damaging bird-aircraft strikes that have resulted in loss of human lives, injuries, and substantial financial losses. Goose poop in a pond greatly increases the degree of chemical and bacterial remediation required to maintain a healthy pond environment. The costs for treating a pond with such chemicals and beneficial bacteria are significantly increased due to the presence of geese, and thus, by having a goose deterrent system as described herein, the ability to maintain a healthy pond is tremendously enhanced.
Such accidents cause annual damages that have been estimated at $700 million within the United States alone and up to $1.2 billion to commercial aircrafts worldwide. Additionally, damages in and around the facilities and aircrafts where birds nest and congregate cost millions of dollars in the man-hours needed for bird strike prevention and clean-up.
No Federal or State wildlife permit is required to harass geese, as long as they are not handled, harmed or killed. Many ways have been attempted to deter geese, with mixed success. Habitat modifications include alteration of vegetation and bodies of water to remove their attractiveness for geese. Unfortunately habitat management may also adversely affect the usefulness of the property for its intended purpose. Two chemical formulations are registered with the U.S. EPA as Canada goose taste repellents: methyl anthranilate (MA) and anthraquinone. The cost of the material (approximately $150-250/acre of grass) is cost-prohibitive for widespread use on private lawns. Past bird dispersal techniques also included the use of high volume audible alarms or explosives to disperse birds. These devices, however, are limited to rural areas where the intense noise did not disturb residents and are of only arguable effectiveness. Other examples of typical methods include reducing grassy areas, using shrubbery and foliage to cordon off water bodies, installing fences, utilizing noise makers to scare the geese away, and flavoring the grass with distasteful substances.
Many of the above recited methods are impractical, as reducing grassy areas and surrounding water hazards with shrubbery is inconsistent with the purpose of a golf course or athletic field. Utilizing noise makers such as cap guns or the discharge of blank shells necessarily upsets the serenity of these locations for humans as well as geese. U.S. Pat. No. 7,699,018 to Wells employs the use of solar powered lights to attempt to deter geese, but such lights are typically amber in color, have an industrial aesthetic appearance in otherwise pastoral settings, are expensive and their flashing yellow/amber light at dusk and through the night have caused neighbors to complain as to the annoyance created by such lights, adversely affect the quiet enjoyment of property owners, including even the owners of such lights. U.S. Pat. No. 8,667,930 to Homung is directed to an apparatus to avert waterfowl settlements that includes an elongated tubular housing having an end cap, a solar panel mounted on top of the housing cap to recharge a battery power source and a means to sense ambient light for device activation, preferably including bird spikes mounted atop a solar collector panel. Similar to Wells, however, the type of light used by Homung, creates an eyesore in a setting where such an unsightly addition defeats much of the purpose for many residents of having a water feature.
Other prior art methods have proven difficult to use for various reasons. Chemical repellants are expensive, have limited residual effect and may have currently unknown environmental consequences. Noise makers, such as air cannons, are not welcomed in residential areas and it is believed that they are of limited use because waterfowl adapt quickly to the sounds. Balloons and Mylar tape barriers are eyesores, distract from natural settings, are of controversial value and seem to offer limited results. Birds quickly learn that the playing of recorded distress calls is a false alarm and thereafter tend to avoid such warnings.
Thus, there have been many and varied approaches to deter geese from populating certain areas, all of which have mixed results in terms of effectiveness. Any means to limit the number of geese in particular areas and to reduce the associated damages they cause, would be of great value.